Photocatalytic [4 + 1] Cycloaddition Access to Multisubstituted 2-Imino-2,5-dihydrofurans
Shan-Shan Li1, Hong-Yu Yang1, Zhi-Peng Ye2
1School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, P. R. China.
Organic Letters
|September 1, 2025
Summary
Researchers developed a new isocyanide radical cyclization method for complex molecules. This strategy enables the synthesis of novel 2-imino-2,5-dihydrofuran derivatives with potential anticancer applications.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Synthetic Chemistry
Background:
- Isocyanide radical cyclization is usually limited to aryl isocyanides.
- Complex radical precursors often hinder these reactions.
- A need exists for broader applications and simpler synthetic routes.
Purpose of the Study:
- To develop a novel strategy for isocyanide radical cyclization.
- To extend the scope of this reaction to alkyl and biomolecule-derived isocyanides.
- To synthesize diverse 2-imino-2,5-dihydrofuran derivatives and evaluate their potential applications.
Main Methods:
- Integration of [4 + 1] cyclization with a multifunctional system.
- Utilizing novel radical precursors for isocyanide cyclization.
- Synthesis and characterization of over 50 2-imino-2,5-dihydrofuran derivatives.
Main Results:
- Achieved a rare 1,2,3,4-tetrasubstitution of α,β-unsaturated carbonyls.
- Successfully synthesized a wide range of 2-imino-2,5-dihydrofuran derivatives.
- Demonstrated the molecular skeleton editing capability into valuable frameworks.
Conclusions:
- The developed strategy overcomes limitations in isocyanide radical cyclization.
- The synthesized derivatives exhibit significant antitumor activity.
- These compounds hold promise for future drug development in oncology.
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